I have a Brooks B17, a Selle Anatomica, and have ridden a Selle SMP to review for purchase. If I were you, I would look at the SMP Web site, figure out which model would suit, and buy one. Expensive yes, but addresses your (critical) issue directly.

From their website: The central channel of the saddle is an uncommon characteristic because of its dimensions: almost a whole hand can be put in there and this prevents crushing of the anus, prostate, venae pudendae, deep dorsal vein and artery of the penis, scrotum and testicles in men, and the labia majora and minora and the clitoris, in women.

The cyclist’s seating pattern on the SMP4BIKE saddle is shared between the buttocks and the lower part of the pelvic bones (the ischial tuberosities) and the position is favoured by the shape of its rear which, besides preventing squashing of the coccyx on uneven ground, allows gentle ins and outs from the rear when the ground requires it.